Hybridization Gap and Dresselhaus Spin Splitting in EuIr4In2Ge41. (25th June 2015)

• Record Type: Journal Article
• Authors: Calta, Nicholas P.; Im, Jino; Rodriguez, Alexandra P.; Fang, Lei; Bugaris, Daniel E.; Chasapis, Thomas C.; Freeman, Arthur J.; Kanatzidis, Mercouri G.
• Is Part Of: Angewandte Chemie. Volume 127:Number 32(2015)
• Page Start: 9318
• Page End: 9323
• Publication Date: 2015-06-25
• Subjects: Chemistry -- Periodicals; 540
• DOI: 10.1002/ange.201504315
• Languages: English
• ISSNs: 0044-8249

Abstract

<abstract abstract-type="main" xml:lang="en"> <title>Abstract</title> <p>EuIr₄In₂Ge₄ is a new intermetallic semiconductor that adopts a non‐centrosymmetric structure in the tetragonal <inline-formula><alternatives><tex-math notation="tex"><![CDATA[${I\bar 42m}$]]></tex-math><inline-graphic xlink:href="ark:/27927/pgj270gb7rt" mimetype="image" xlink:type="simple" xmlns:xlink="http://www.w3.org/1999/xlink" /></alternatives></inline-formula> space group with unit cell parameters <italic>a</italic>=6.9016(5) Å and <italic>c</italic>=8.7153(9) Å. The compound features an indirect optical band gap <italic>E_g</italic>=0.26(2) eV, and electronic‐structure calculations show that the energy gap originates primarily from hybridization of the Ir 5d orbitals, with small contributions from the Ge 4p and In 5p orbitals. The strong spin–orbit coupling arising from the Ir atoms, and the lack of inversion symmetry leads to significant spin splitting, which is described by the Dresselhaus term, at both the conduction‐ and valence‐band edges. The magnetic Eu²⁺ ions present in the structure, which do not play a role in gap formation, order antiferromagnetically at 2.5 K.</p> </abstract>